Lubricants



Patented Jan. 5, 1954 2,665,252 OFFICE LUBRICANTS Carl F. Prutton, Cleveland Heights, Ohio, assignor to The Lubrizol Corporation, Wicklifie, Ohio, a

corporation of Ohio No Drawing. Application September 25, 1948, Serial No. 51,306

Claims. (Cl. 252-33) This application is a continuation-in-part of Serial No. 51,307, filed September 25, 1948, now Patent No. 2,555,370 and Serial No. 51,309, filed September 25, 1948, now Patent No. 2,555,311.

This invention relates as indicated to lubricants and particularly to lubricating compositions which have been improved as to detergenoy and corrosiveness by the inclusion therein of a minor amount of a metal salt of a compound selected from the class consisting of those which contain a plurality of groups represented by the formula RSOsX, such groups being interconnected by at least one atom of sulphur, and in which R is a wax substituted diphenyl oxide group, and X is the hydrogen equivalent of a metal. More particularly, this invention relates to metal salts of the Inonosulphide and disulphides of Wax substituted diphenyl oxide sulphonic acids.

It is, therefore, a principal object of my invention to provide a lubricating composition which has the desirable characteristics of reduced tendency to the deposition of deleterious deposits, and a reduced tendency to corrode the metal parts with which such lubricants come in contact.

Further object of my invention is to provide a method of improving a lubricant with respect to its detergent and corrosion properties by including therein a minor amount of a metal salt of sulphide or poly sulphide of wax substituted diphenyl oxide sulphonic acids.

Other and more specific objects of my invention will appear as the description proceeds.

To the accomplishments of the foregoing and related ends, the invention, then, comprises the features hereinafter fully described and particularly pointed out in the claims, the following description setting forth in detail certain i1- lustrative embodiments of the invention, these being indicative, however, of but a few of the various ways in which the principle of the invention may be employed.

Broadly stated, my invention maybe described 'as a lubricating composition comprising a major amount of an oil of lubricating viscosity and a minor amount of a compound selected from the class consisting of those which contain a plurality of groups represented by the formula 'RSOaX, such groups being interconnected by at least one atom of sulphur, and in which R is a wax substituted diphenyl oxide group and X is the hydrogen equivalent of a metal. It becomes convenient therefore to describe specifically how the wax substituted diphenyl oxide sulphonate monosulphides and disulphides or higher poly sulphides, of this invention are prepared.

Example 1* 1925 grams of diphenyl oxide are mixed with 800 grams superfiltrol an acid treated clay cata lyst and heated to 210-'220 C., 5575 grams of wax unsaturate are added to the hot solution over a period of about 15 minutes, the temperature of the mixture being maintained during the addition period at 210-220 C. After the addition has been completed, the temperature is raised to 225-235 C. and there maintained for 2.5 hours. The product thus produced is filtered through hot cloth with the aid of Hyflo a diatomaceous earth filter aid. The yield of wax substituted diphenyl oxide was 78.3%.

Example 2 1700 grams of diphenyl oxide, 800 grams of superfiltrol and 160 grams of zinc chloride are mixed in a flask and heated to 170 C. The amount of zinc chloride is 3.5% by weight of the chlor wax to be added. 4500 grams of 18% chlor wax are added over a period of 90 minutes. The temperature of the mixture is maintained at 170 C. for one hour after which time it is increased to 240 C. and there maintained for two hours. The product thus obtained is then filtered with the aid of Hyflo. The filtrate is stripped to 225 C. at 2 mm. Hg absolute pressure. This product contained a trace of chlorine.

Example 3' 856 grams of wax substituted diphenyl oxide prepared in accordance with Example 1 or 2 above are dissolved in 400 cc. of ASTM naphtha. To this mixture are added 198 grams of chloro sulphonic acid at about room temperature. During such addition, the temperature rises to about C. The mixture is then stirred for one hour at C. At the end of this period, 109.2 grams SzClz are added at a temperature of 50-60 C., and the mixture then stirred for two hours at 60-'70 C. At this point the acid number of the reaction product was found to be 75.0. 1295 grams of an SAE 10 oil, 100 cc. of methyl alcohol and a 20% excess of calcium hydroxide (82 grams) are added and the mixture stirred for two hours at -90" C. Thereafter the mixture was dried at -100 C. and became solid. Then two liters of benzene were added and the mixture further dried under reflux. grams of a diatomaceous earth filter aid were added and theproduct filtered until clear. The filtrate was vacuum distilled at 150-160 C. and 50 mm. Hg

122 grains of chloro sulphonic acid were added in dropwise fashion to 530 grams of wax substituted diphenyl oxide as described above in Ex- 68 grams of S2Cl2 were added at 55-65 C. and the mixture stirred one hour. The J ample 3.

product at this point had an acid number of 94.5. 43.3 grams of sodium hydroxide were added to 30 cc. of water and the solution added to the acidic material. Upon each addition, the material became very viscous and two liters of a butyl alcohol solution in lactol spirits were added. The mixture was stirred for two hours at 80-90 C. and water was removed by means of a water trap under reflux conditions. The product was then filtered and the solvent removed at 165 C. at a pressure of 2 mm. Hg. The residue was a dark brown lumpy solid having no odor. Upon analysis this product was found to contain 7.6% sulphur, had an acid number of 6.53 and a calcium sulphate ash of 10.3%. This material was found to be unsoluble in oil.

This product may be conveniently used as an intermediate in the preparation of heavier metal salts by the well-known process of double decomposition.

Eramplc 5 The disulphide of wax substituted diphenyl oxide sulphonic acid was prepared in the same manner as outlined above in Examples 3 and 4 using 88 grams of wax substituted diphenyl oxide, 20.3 grams of chlorosulphonic acid, and 11.3 grams of S2C12; with the exception that 88 grams of a 70-5 vis. oil were added prior to the S2012 treatment step. Following the conversion to the disulphide, 148 grams of the same oil were added to the mixture together with cc. of methyl alcohol and 22.2 grams of barium carbonate excess). This mixture was heated at 70 C. until it became thick, at which time two liters of benzene were added. The solution was stirred for three hours at 70-80 C. The solvent was evaporated at 160 C. at 50 mm. pressure. grams of capryl alcohol were added and additional solvent to facilitate filtration. Filtration was found to be very difficult. The solvent was removed to a temperature of 120 C. at a pressure of mm. Hg. The resultant product was a jell-like solid having a dark brown color and no odor. It was soluble in neutral oil at concentration of 50%, 10% and 1% and showed no tendency to settle out upon standing for a period or one month. This product analyzed 2.52% sulphur, had an acid number of 3.88, and a calcium sulphate ash of 3.85%.

Other salts of these acids may be prepared by treating the sulphonic acid with lime, sodium hydroxide, barium hydroxide, zinc oxide, and other such commonly employed neutralization reagents. These reagents may be used where it is desired to directly neutralize the acid. As indicated above, it may be convenient to first prepare the sodium salt of the acid and then by double decomposition produce such metal salts as the cobalt, copper, iron, lead, etc. salts.

Although the foregoing examples illustrate the preparation of the disulphides as. resulting from the use of S2012 as the sulphiding reagent, it is clear that the mono sulphides may be prepared by using the proper molar quantity of S2012. Moreover, it is clear that the higher poly sulphides may be prepared by treating the disulphides, for example, with a sulphur imparting reagent such as elemental sulphur, or the sodium poly sulphides. In this manner the sulphide bridge may be increased to as many at 6 atoms of sulphur.

Throughout the foregoing discussion, reference will be had to wax-substituted dip e y ether (or oxide). It is recognized that wax, particularly parafiin wax, is. a. highly comp hydrocarbon. Furthermore, upon halogenation a complex mixture in which there are molecules of wax containing no chlorine, and others containing one, two, three, four and possibly more halogen atoms. Processes have been developed whereby monochlor wax, dichlor wax, etc., may be separated from such a crude mixture involving fractional crystallization means (see Patent No. 2,218,132).

The paraflin wax molecules contain more than 20 carbon atoms, generally about 24 to about 30 carbon atoms. Thus where I have employed chlorinated paraffin wax containing about 20% chlorine, it is seen that such molecules contain about 2 chlorine atoms per molecule. Accordingly, since the chlorine atom is the reactive point of the molecule in the alkylation reaction, the number of moles given in the examples is actually the number of gram equivalents of chlorine in a given weight of chlorwax and not the actual number of moles of chlorwax. This will be evident by calculations from the percentage of chlorine in the wax. Likewise, where such a chlorwax has been dehydrohalogenated, the same basis for calculating the number of moles has been used, such number referring to the number of gram equivalents of unsaturation present.

Therefore, strictly speaking, the Wax substituted diphenyl ether to which I refer is in many instances a polydiphenyl ether substir' tuted wax, i. e. a wax group having a plurality of diphenyl ether groups attached thereto. In a preferred case, I employ the equivalent of about 2.5 grams equivalent weights of chlorine per diphenyl ether group, although I have made products containing a lower proportion of wax as well as higher proportions.

The foregoing methods of preparation are given by way of illustration only and are not to be construed as limiting the invention to the precise method of preparation disclosed.

When used in amounts ranging from about .5% to about 10% by weight of the oil in which it is incorporated, these salts of Wax substituted diphenyl oxide sulphonic acid, sulphides and poly sulphides demonstrate a marked improvement in the detergent and corrosion properties over that which is obtained when using the untreated base oil. In a more particular refinement of my invention I have found that I am able to further reduce the corrosive tendencies of the lubricant by including therein, in addition to the metal salt of the wax substituted diphenyl oxide sulphonic acid sulphides or poly sulphides, a minor amount of an inhibitor material. The unusual result obtained here is that not only is there a marked improvement in the reduction of the amount of corrosion, but there is also a great improvement in the amount of detergency exhibited by the finished lubricant blend. Such additional inhibitor materials are generally used in amounts less than 5% and generally on the order of from about .1% to about 3% by weight ofthe total blend. These inhibitors are generally phosphorus-containing, and more particularly phosphorus and sulphur containing materials in which the sulphur is in such form that when thus included in the lubrieating composition it is of intermediate reactivity; that is such sulphur does not react with a metal of the class consisting of copper and iron at temperatures below 0., but will react substantially therewith at temperatures between 100" C. and 250- C. Suitable inhibitors of the foregoing types are the poly vaient metal salts of the reaction product of P285 with an alcohol in a molar ratio of from about 1:4 to about 1:5. The alcohols thus employed are generally 6 In the Lauson engine test, the lubricant is tested for the indicated number of hours at the end of which time the condition of the piston and the bearings is determined. The condition aliphatic alcohols and desirably cycloaliphatic 5 of the piston skirt is indicated by a capital letter alcohol such as methyl cyclohexanol, propyl cyranging from A which denotes a clean piston is clohexanol, amyl cyclohexanol, etc. These redevoid of any deposits, to E which denotes a action products are highly acidic and may be black, heavily coated piston. The second figure conveniently neutralized by ordinary neutralizais the number of compression rings which are tion methods with such basic materials as barium stuck so that they are not free to move in the oxide, barium carbonate, zinc oxide, zinc carbolands. The third figure indicates the percentage nate, calcium oxide, calcium hydroxide, etc. of filling which is observed in the oil ring. Such Thus I may prepare the barium, calcium, mag filling is an indication of the amount of sludge nesium, zinc, copper, etc. salts. and other decomposition products which form I may also use as inhibitive addents reaction during the operation of the engine which are products of phosp d u p ur Co taining incapable of being removed by the action of the reagents with unsaturate materials such as, for detergent, The fourth figure represents the exam-191e, reaction product of 4 {110165 0f loss in weight in milligrams of the bearing, and pentme with one mole of P 2S5, or like materials giVeS an indication of the corrosiveness of the produced in accordance with the teachings of lubricant. my apphcatlon 52101548 filed July In the Chevrolet test, the engine is running 1944, and my application Serial No. 544,633, filed July 12 1944 now abandoned at about 3000 R. P. M. for a period of 36 hours at the end of which time the engine is dismantled The following tables illustrate the utility of and examined as to condition of the bearm S the metal salts of wax substituted diphenyl oxide 1 t t sulphonic acid disulphides alone and in combi- 01 81 e 6 and mg nation with various inhibitors. These examples based observatlons of an of these parts are by way of illustration only and are not to be determmed wlth. 1.00% repreentmg maxl' construed as limiting the invention to the spethe plston 3 15 rated cific materials named or the indicated amount numerlcany W h 10 being the maximum. The thereof which may be employed, other figures shown in the following table repre- The utility of these materials has been desent the loss in Weight in milligrams of the top termined by actual engine tests on either the half and the bottom f f tWO rod bearings Lauson six cylinder engine or in a standard six selected at random. A ratin of fr t0 cy1inder Chevrolet. en in 95% is a very satisfactory over-all engine rating.

Lauson engine Chevrollltztueiiglue (36 Metal Salt of Piston n b t't t d Pg 3511 315125159 fig; Inhibitor 5: f j Oversulphonic acid ercerit sulphides Hours ring mung To '1 piston p op filling I an half, half, bearing a g bottom bottom loss half half i Calcium s1 1.0 Capryl-a-naphthol 1.0 240 8 so 0 2 do 1.0 Phenylethyl-b-naphthol 1.0 240 8 I BO 80.5 29 a1 3 do 1.0 Oapryl resorcinol 1-0 240 g 86 61 4 do 0.8 Tributylphosphite 0.4 :1? 5 do 0.8 Lithium di-(capryl cyclohexyl) di- 0.83 g 5 thiophosphate. 5 29 31 6 d 0.3 Zinc di-(methy1cycl0he Y i 29 a phosphate. 931 0 13 14 7 (10 1.09 d0 9 5 50 39 s do 1.59 Pass-treated turp ti 31( 1% 9 -do 0.8 Diisobuteiiylnaphthenate-Pzsi(4:1). 0.5 0

176 m 11 do 1. 59 g; 12 --do 2.39 5:? 22 13 d 0,8 Barium salt of Pass-treate me hy cyclohexanol. 7 5 4 45 14 do 1.59 do M85 815 4s 39 15 Barium (S2) 2.0 Barium salt oi PiSi-treated methyl 0 57 89.5 80 73 cyclohexanol, end Past-treated 8.5 69 93 turpentine.

1s Cobalt(0us) ea 1.66 Barium salt OlPflSs-tlfiflted methyl 9.51 240 g 9 131 cyclohexanol. m5

The foregoing tests demonstrate thatlubricant compositions prepared in accordance with this a base oil with respect to detergency and corrosion comprises adding thereto minor amounts of metal salts of Wax substituted diphenyl oxide sulphonic acid sulphides or poly sulphides. Such data also show that a cooperative effect is obtained in the combined use of the principal addition agent and a separate inhibitor material of the types above described. ,7 Other modes of applying the principle of the invention may be employed, change being made as regards the details described, provided the 'features stated in any of the following claims,

or the equivalent of such, be employed.

I therefore particularly point out and dis- =tinctly claim as -my invention:

1. A lubricating composition comprising a major amount ,of an-oil of lubricating viscosity and about 0.5 to 10% of a metal salt of parafiin wax-substituted diphenyl oxide sulphonic acid sulphide.

2. A lubricating composition comprising a major amount of an oil of lubricating viscosity and about 0.5 to 10% of a metal salt of paraffin wax-substituted diphenyl oxide sulphonic acid disulphide.

3. A lubricating composition comprising a major amount of an oil of lubricating viscosity and about 0.5 to 10% of a polyvalent metal salt of paraiiin wax-substituted diphenyi oxide sulphonic acid sulphide.

4. A lubricating composition comprising a major amount of an oil of lubricating viscosity and about 0.5 to 10% of a polyvalent metal salt of paraflin wax-substituted diphenyl oxide sulphonic acid disulphide.

5. A lubricating composition comprising a major amount of an oil of lubricating viscosity and about 0.5 to 10% of an alkaline earth metal salt of paraffin wax-substituted diphenyl oxide sulphonic acid sulphide.

6. A lubricating composition comprising a 8 major amount of an oil of lubricating viscosity and about 0.5 to 10% of an alkaline earthmetal salt of paraffin wax-substituted diph'enyl oxide sulphonic acid disulphide.

7. A lubricating composition comprising a major amount of an oil of lubricating viscosity and about 0.5 to 10% of the calcium salt of paramn wax-substituted diphenyl oxide sulphonic acid disulphide.

8. A lubricating composition comprising a major amount of an .oil of lubricating viscosity, about 0.5 to 10% of a polyvalent metal salt of paraffin wax-substituted diphenyl oxide sulphonic acid sulphide and about 0.1 to 3% of the product obtained by reacting turpentine With a phosphorus sulfide at a temperature of more than about 100 C.

9. A lubricating composition comprising a major amount of an oil of lubricating viscosity, about 0.5 to 10% of an alkaline earth metal salt of parafiin wax-substituted diphenyl oxide sulphonic acid disulphide, and about 0.1 to 3% of the product obtained by reacting turpentine with P285 at a temperature of more than 100 C.

10. A lubricating composition comprising a major amount of an oil of lubricating viscosity, about 0.5 to 10% of the calcium salt of parafiin Wax-substituted diphenyl oxide sulphonic acid disulphide, and about 0.1 to 3% of the product obtained by reacting in the order of about 4 moles of turpentine with in the order of about 1 mole of P235 at a temperature of more than about 100 C.

CARL F. PRUTTON.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,197,835 Reiff Apr. 23, 1940 2,244,512 Brandt June 3, 1941 2,316,087 Gaynor Apr. 6, 1943 2,316,091 White Apr. 6, 1943 2,411,583 McNab et al. Nov. 1946 2,465,902 McNab et al. Mar. 29, 1949 2,493,217 Berger et al. Jan. 3, 1950 

1. A LUBRICATING COMPOSITION COMPRISING A MAJOR AMOUNT OF AN OIL OF LUBRICATING VISCOSITY AND ABOUT 0.5 TO 10% OF A METAL SALT OF PARAFFIN WAX-SUBSTITUTED DIPHENYL OXIDE SULPHONIC ACID SULPHIDE. 